Tension-releasing device for sewing-machines.



t A. H. DE vos. TENSION RELEA'SING DEVICE FOR SEWING MACHINES.

APPLICATION FILED 0CT.29| l9l3 Patented July 13, 1915.

fran amarres 'elegant e ALBERT H. DE VOE, 0F WESTFIELD, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

TENSION-RELEASING LEVICE FOR SEWING-MACHIN ES.

Specification of Letters Patent.

Patented July 13, 1915.

Application filed October 29, 1913. Serial No. 797,945.

leasing Devices for Sewing .Machines, of

which the following is a specification,- reference. being had therein to the accompanying drawings.

This invention has for its object to provide a multiple-needle sewing machine with simple Aand effective means whereby the presser-foot may be lifted and the pressure of the thread-e-ngaging tension-devices simultaneously released, when it is desired to remove work from the machine.

` TheA invention consists essentially of a movable support for the tensiondevices comprising a plate provided with apertures to receive the hollow threaded Shanks of a,

series of split spindles, each of which supports 'two spring pressed thread-engaging disks. The hollow shank of `each spindle receives a pin to engage awasher interposed between a pressure spring and the thread-engaging disks, said pins normally projecting beyond the face of the supporting plate. The supporting plate lis connected to a sliding rod journ'aled in a boss formed upon the upper face ofthe sewing machine standard, said rod being engaged by an elbow-lever throughwhich it is moved longitudinallyto carry the supporting plate toward an adjacent contact plate, whereby the pin of each tension-device is engaged by said plate, and the washer and spring held against bodily movement while the threadengaging disks are retracted therefrom.

lThe elbow-lever is pivotally supported upon the sewing machine standard and is endevices, the supporting plate, and their c'on-` nections with the presser-foot lifting rockarm.

The device is shown applied to a multiple-needle sewing machine of the Singer type provided with the bed-plate A, standard B, overhanging-arm C and head D. In the head D is j ournaled a reciprocatory needle-bar 1 provided with multiple needleclamp 2 carrying, in the present instance, four needles.

In the head D of the machine is journaled the presser-bar 3 provided with the presserfoot -l and carrying near its upper end' a collar 5 provided with lateral stud 6, said stud supporting a friction-roller 7 engaged by the forward end of rock-arm 8 pivotally connected,'by means of threaded fulcrum-stud 9, to the overhanging-arm C of the machine, and provided at its opposite end with an opening 10 to receive treadlechain 11 by which the arm is rocked'upoii its fulcrum-stud 9 to lift the presser-foot.

Upon the upper face of the standard B, and transversely thereof, is formed a boss 12 in which is journaled a sliding-rod 13 fixed at one end to a supporting plate 14 for the tension-devices. In the present instance, supporting plate 11 is formed with a curved upper edge 15 merging into a laterally projecting arm 1G and is provided with a substantially rectangular'base portion 15",'the

latter supporting four tension-devices for` the looper threads, four tension-devices for the needle-threads being supported by the pla-te along its curved upper edge and arm in slightly off-set relation to each other.

Each tensiondevice comprises a split spindle 17 having a hollow hub 18 secured within an aperture formed in the supporting plate 14. The hub of each spindle is provided with a collar 19 which bears against a thread-guiding disk 20 supported by said hub adjacent the plate 14 and formed with an outwardly bent lip having a threadaperture. rThe spindle 17 supports at the outer face of collar 19 two tension-disks or plates.17X movable upon said spindle relatively to the plate 14 and between which the 'needle-thread is passed to produce tension thereon. Next to the tension-disks 17X the 'split spindle receives a lifting washer 21, said lifting washer having two like apertures toreceive the two halves of the spindle, a narrow cross-bar 22 separating the said two apertures and lying in the slit between the two halves of the spindle. Intermediate washer 21 and a nut 23 applied to the threaded outer end of the-spindle 1s -a spring 24, the outer end of which, as indicated in Fig. 2 of the drawings, passes into the slitted end of the spindle.

'ithin the hollow-hub 18 of each spindle is a pin 25 one end of which engages the cross-bar 22 of the spring-lifting washer, its other end normally projecting beyond the face of supporting plate 14. It will be seen that pressure upon the projecting end of pin 25 will move washer 21 against the stress of spring v24 and thereby release the tension-disks 17X from the pressure of said spring. Intermediate supporting plate 14 and the standard B, and fixed to the latter, 1s a contact plate 26 similar in shape to the supporting plate 14, the end of the laterally extending arm 26 of the contact plate carrying a guide-stud 27 adapted to enter an aperture formed in the arm 16 of the supporting plate. The stud 27 serves to prevent lateral movement of the supporting plate 14 and thus to maintain said plate in register with contact plate 26.

Therearward end of rod 13 is formed wi-th a vert-ical channel 28 to receive one arm 29X of an elbow-lever pivotally secured by means of a stud 30 to the lateral. projection 31 of the standard B. The rearward end of rock-arm 8 is provided with an aperture to receive upwardly extending rod 32 said rod being securedl in said aperture by clamping screw 33, its upper portion being bent at right angles to overhang arm 29 of the elbow-lever.

It Will be seen from inspection of the drawings that actuation of rock-arm 8 by means of a treadle or other device to lift the presser-foot, will move rod 32 downwardly thereby bringing the rounded engaging face of elbow-lever 29X into engagement with shoulder 34 of sliding rod 13, thus moving the rod in its boss 12 to carry the supporting plate 14 toward Contact plate 26, whereby the pin of each tension-device engages said plate and acts, through washer 21, as a stop device to hold spring 24 as the thread-engaging disks are retracted therefrom by the movement of the supporting plate. By such movement, the parts assume the position shown in F ig. 2.

It will be understood that the present in- .vention is not limited to the precise embodiment thereof herein shown and described. For instance, any suitable supporting means may be used for the tension-devices, and means acting independently of the presserfoot may be employed to lactuatesaid support.

It is evident that the specific form and construction'` of the tension devices is not essential tol the present improvement, and

that the .tension devices herein shown and described may be simplified or otherwise modified in construction without departure from the invention.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine,.the combination with a supporting plate, of a tension-device comprising a thread-engaging member carried by and movable relatively to said plate, a spring normally exerting pressure upon said thread-engaging member, a stop device for said spring, a contact member for the stop device and means for moving said supporting plate relatively to said stop device to carry theA thread-engaging member beyond the range of action of said spring.

2. In a sewing machine, the combination with a presser-foot and a lifting arm therefor, of aplurality of tension-devices each comprising a. movable thread-engaging member, a common movable support for said thread-engaging members, a series of springsl each normally exerting pressure upon an thread-engaging member, a stop device for each spring, and means actuated by said lifting arm for moving theisupport relatively to said springs.

3. In a sewing machine, the combination with a presser-foot and a lifting arm therefor, a plurality of tension devices each comprising a thread-engaging member movable upon a spindle vunder the pressure of a. spring', a common movable support for said tension-devices, and means including said lifting arm for reti-acting said support to carry each thread-engaging member beyond the range of action of its spring.

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4. In a. sewing machine, the combination f i arm for moving said support relatively to the contact member.

5. In a sewing machine, the combination with a presser-foot and a lifting arm therefor, of a plurality of tension-devices each comprising a movable thread-engaging member, a series of springs each normally exerting pressure upon a thread-engaging 'member, a stop device for each spring, a

common movable support for said tensiondevices provided with a laterally projecting rod, an elbow-lever operatively connected to said rod, and a connection between said elbow-lever and the lifting arm whereby actuation of the latter will bodily move said supporting plate to carry eac-h thread-eniaef gaging member beyond the range of action of its spring.

6. In a sewing machine, the combination with a movable support, of a tension-device 5 comprising a thread-engaging member carried by and movable relative to said support, a spring adapted to act upon said thread-engagingmember, a stop device for said spring, a contact member for the stop 10 device, and means for moving said support to cause the thread-engaging member to assume positions respectively Within and beyond the range of action of said Spring'.

In testimony whereof, I have signed my name to this specification, in the presence of 15 two subscribing Witnesses.

ALBERT H, EE VUE. `Witnesses:

WVM. P. STEWART, H. A. KORNEMANN, Jr.

Gopies of this patent'may be obtained for ve cents each, by addressing the Commissioner of atents,

Washington, D. C. 

